Severe Thunderstorm Warning 12, NWS Las Vegas, NV

Area Forecast Discussion
National Weather Service Las Vegas NV
212 PM PDT Thu Jun 15 2023

.SYNOPSIS...Showers and thunderstorms will continue across parts
of the region tonight and Friday in areas generally north of
Interstate 40. There is some possibility of isolated showers and
storms in parts of our southern deserts on Friday. Expect partly
to mostly cloudy skies and cooler temperatures on Friday with
mostly clear conditions and warmer temperatures over the weekend.
Las Vegas will be looking for its first 100 degree day of the
year this weekend. A low pressure system will bring windy
conditions to the area Sunday and Monday. Well below normal
temperatures will return on Monday and continue through at least
the middle of the week.

&&

.DISCUSSION...Tonight through the weekend.

A low pressure system to our north is forecast to drop southward
tonight while a second system over the eastern Pacific advances
towards southern California. Dynamics associated with these
systems will bring an increased chance for nocturnal convection
across parts of the area through the overnight hours. Areas
affected include the southern Sierra and Owens Valley, portions of
Death Valley National Park, southern Nye and Lincoln counties,
Clark County, and northern Mohave County. Stronger storms
will be capable of producing frequent lightning, strong outflow
winds over 40 mph and brief heavy rainfall. The two systems are
forecast to merge over our forecast area on Friday leading to
another round of showers and thunderstorms. Our western areas will
see chances decreasing through the morning hours on Friday with
the focus area for afternoon storms shifting to Lincoln, Clark,
and northern Mohave counties. Shower and storm activity is
expected to end around sunset Friday evening.

Dry conditions are expected over the weekend with temperatures
warming back to around normal for mid June. For Las Vegas, highs
are forecast in the upper 90s both Saturday and Sunday but there
remains an outside chance reaching our first 100 degree temp of
the year at Harry Reid International Airport, the official
reporting site in Las Vegas. The latest NBM probabilities give a
11/22 percent chance of reaching that century mark on Saturday and
Sunday, respectively. If 100 degrees isn't recorded, the next
opportunity presents itself late next week but even those chances
are decreasing compared to what they were yesterday. Looking at
the 6-10 day and 8-14 day outlooks from CPC, there is a 40 percent
chance or higher of temperatures remaining below normal through
at least the 28th of June. The primary concern for the weekend are
increasing winds on Sunday as the next system approaches the
area. Widespread windy conditions are forecast with gusts 25-40
mph. There could be a need for wind headlines for Sunday,
especially in the Western Mohave Desert where the NBM gives a 40
percent or higher chance of gusts reaching 40 mph or greater.

Monday through Thursday next week...

A low pressure system is forecast to move into the Pacific NW and
northern Great Basin on Monday and linger into Tuesday. Widespread
gusty southwest winds 25-40 mph continue with the area for the
highest gust potential shifting to eastern Lincoln County. With
the low center forecast as far north as it is, precipitation
chances are nil and the forecast is dry for all our areas.
Temperatures will drop on Monday with highs forecast to be around
5 degrees below normal across the area. Dry conditions will
continue on Tuesday but winds are expected to be much lighter.
Temperatures lower several more degrees with highs around 10
degrees below normal.

There is good ensemble agreement with troughing over the west
through at least Thursday. The trough axis is forecast to be
generally aligned with the coastline which gives us a southwest
upper level flow both Wednesday and Thursday. This should allow
temperatures to rebound but still remain around 5 degrees below
normal. General afternoon breeziness is possible with no
significant winds expected based on the latest model data.

&&

.AVIATION...For Harry Reid...Scattered showers and isolated
brief thunderstorms around the Las Vegas Valley may temporarily
impact the terminal area with gusty and erratic winds through late
this afternoon. Winds will be driven by outflow from showers and
will likely come from the southeast through this afternoon then
north or northeast over 10 knots after 03Z this evening through
Friday morning. Gusts to 30 knots will be likely near showers.
Periods of showers and thunderstorms will occur late tonight through
Friday morning as an upper level disturbance provides support for
nocturnal showers and storms with continued gusty and erratic winds
due to outflow from showers.

For the rest of southern Nevada, northwest Arizona and southeast
California...Scattered showers and thunderstorms will expand in
coverage across southern Nevada and southern Inyo County California
late this evening and overnight. This will mainly impact TAF sites
in the Las Vegas Valley with periods of showers and thunderstorms
and gusty and erratic winds to 30 knots.

&&

.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.

&&

DISCUSSION...Salmen
AVIATION...Adair

For more forecast information...see us on our webpage:
https://weather.gov/lasvegas or follow us on Facebook and Twitter